managed_file form component not submitted on AJAX submit

Hello,

While trying various things with the Forms API and AJAX, I stumbled on a problem which occurs when managed_file form element and AJAX submit are used on the same form. Here are my tests

• when form has no AJAX behavior:
  • choose a file to upload, then click on the element "upload" button before clicking on submit button : OK, file was uploaded
  • choose a file to upload, do not click on the element "upload" button, directly click on submit button : OK, file was uploaded too
• when form submit button has #ajax properties:
  • choose a file to upload, then click on the element "upload" button before clicking on submit button : OK, file was uploaded
  • choose a file to upload, do not click on the element "upload" button, directly click on submit button : NOT OK, file was not uploaded

It seems that the file is not pushed during the AJAX POST request.
You can try by yourself using the little module I attached (module file code is below): http://example.com/ajaxtest displays a simple form (only one managed_file element, and a submit button), without any AJAX behavior for submit button. Using the URL http://example.com/ajaxtest/ajax will add an AJAX callback to the submit button. This way you can easily test the use cases I described above.

Regards,

David Stosik

function mctest_menu() {
  $items = array();

  $items['ajaxtest'] = array(
    'title' => 'File Upload Test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('mctest_ajaxtest_form', FALSE),
    'access callback' => TRUE,
  );
  $items['ajaxtest/ajax'] = array(
    'title' => 'AJAX File Upload Test',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('mctest_ajaxtest_form', TRUE),
    'access callback' => TRUE,
  );

  return $items;
}

function mctest_ajaxtest_form($form, $form_state, $ajax = FALSE) {
  $form = array(
    '#prefix' => '<div id="mctest-form-ajax-wrapper">',
    '#suffix' => '</div>',
  );

  $form['file'] = array(
    '#type' => 'managed_file',
    '#title' => 'Managed file field',
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Submit',
  );
  if ($ajax) {
    $form['submit']['#ajax'] = array(
      'callback' => 'mctest_ajax',
      'wrapper' => 'mctest-form-ajax-wrapper',
    );
    $form['submit']['#value'] = 'AJAX Submit';
    $form['link'] = array(
      '#markup' => l(t('Switch to non-AJAX form'), 'ajaxtest'),
      '#weight' => -10,
    );
  }
  else {
    $form['link'] = array(
      '#markup' => l(t('Switch to AJAX form'), 'ajaxtest/ajax'),
      '#weight' => -10,
    );
  }

  return $form;
}

function mctest_ajaxtest_form_submit($form, $form_state) {
  if (!empty($form_state['values']['file'])) {
    $file = file_load($form_state['values']['file']);
    drupal_set_message(t('File successfully uploaded : %name, %size bytes.', array('%name' => $file->filename, '%size' => $file->filesize)));
  }
  else {
    drupal_set_message(t('No file uploaded!'));
  }
}

function mctest_ajax($form, $form_state) {
  return $form;
}